Fig. 4

Effect of nanostructure and flow rate on microfluidic fuel cell responses. (a) Surface power density of the nickel foam anode at various flow rates. (b) Polarization curves of the nickel foam anode at various flow rates. (c) Maximum surface power density of the nickel foam anode at various flow rates. (d) Surface power density of the nickel nanowires on the foam anode at various flow rates. (e) Polarization curves of the nickel nanowire on the foam anode at various flow rates. (f) Maximum surface power density of the nickel nanowire on the foam anode at various flow rates.